package com.zaicheng.gateway.filter;

import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * 基于全局过滤器实现鉴权
 * @author 张在成
 */
@Component
@Slf4j
public class AccessFilter implements GlobalFilter, Ordered {


    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        String token=exchange.getRequest().getQueryParams().getFirst("token");

        if (null==token){

            log.warn("token is null");

            ServerHttpResponse response = exchange.getResponse();

            response.setStatusCode(HttpStatus.UNAUTHORIZED);

            String msg="{\"message\":\""+HttpStatus.UNAUTHORIZED.getReasonPhrase()+"\"}";

            DataBuffer buffer = response.bufferFactory().wrap(msg.getBytes());

            return  response.writeWith(Mono.just(buffer));
        }
        return chain.filter(exchange);
    }

    @Override
    public int getOrder() {
        return 0;
    }
}
